25x^2+30x+9=16

Solution for 25x^2+30x+9=16 equation:

25x^2+30x+9=16

We move all terms to the left:

25x^2+30x+9-(16)=0

We add all the numbers together, and all the variables

25x^2+30x-7=0

a = 25; b = 30; c = -7;
Δ = b2-4ac
Δ = 302-4·25·(-7)
Δ = 1600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1600}=40$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(30)-40}{2*25}=\frac{-70}{50}
=-1+2/5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(30)+40}{2*25}=\frac{10}{50}
=1/5
$